3898. ----- [WENDER, I., AND ORCHIN, M.] Reduction of Oxygenated Thiophene Compounds. United States Patent 2,587,671, Mar. 4, 1952; appl. filed May 15, 1951, Serial No. 226,520; 9 claims (Cl. 260-332.8).

Method is described for reducing the O-Containing group in an oxygenated thiophene compound selected from the class consisting of thiophene aldehydes, thiophene ketones, and thenyl alcohols, wherein the O atom of the O-containing group is attached to a C atom a to the thiophene nucleus. The compound is reacted with H₂ in the presence of a catalyst chosen from the group consisting of carbonyls of CO and Fe. The preferred temperature and pressure are respectively 110°-200° and 100-300 atm. A concentration of CO in the reaction zone is maintained sufficient to prevent decomposition of the carbonyl catalyst under the reaction conditions. The catalysts for the reaction are cheap and may be formed in situ by adding an organic or inorganic salt of the metal to the reaction mixture where it reacts with CO to form the Co or Fe carbonyl. In the case of Co the active catalyst is probably either dicobalt octacarbonyl [Co(CO)₄]₂ or Co hydrocarbonyl HCo(CO)₄. Cheap hydrogenating gases, such as unpurified water gas or coke-oven gas, may be employed. 3 examples.